Re: COPY locking - Mailing list pgsql-general

From Tom Lane
Subject Re: COPY locking
Date
Msg-id 18190.989512420@sss.pgh.pa.us
Whole thread Raw
In response to COPY locking  (John Coers <coers@intrinsity.com>)
List pgsql-general
John Coers <coers@intrinsity.com> writes:
> I've attached a little facsinating truss output.

You probably shouldn't have sent 250k of trace to the whole mailing
list.  But it *is* fascinating.

I tried to duplicate the result locally with no success.  For a
10000-row COPY FROM STDIN (using the tenk1 table from the regression
database, which has several indexes), my trace contains:

    lseek:    14060
    read:    4261
    write:    4967
    recv:    43
    other:    170

with a large part of the "other" being process startup/shutdown
overhead.  There are no semops or setitimers at all in my trace.
There do seem to be some excess lseeks, but I don't see lots and
lots of seeks with no read or write as you show.

Could we see the schema for the table you are using?
("pg_dump -s -t tablename dbname" is the best way to show it.)

            regards, tom lane

pgsql-general by date:

Previous
From: Justin Clift
Date:
Subject: Re: ER diagrams
Next
From: Ben Carterette
Date:
Subject: my connections never die